They just know the "new" DeMarcus won't be part of the plan for roughly the first half of the season.

Lawrence was drafted early in the second round after the Cowboys triggered a revamping of their defensive front by releasing franchise sacks leader DeMarcus Ware in March.

But the former Boise State player is far from the only newcomer in the group. His absence could mean more shuffling for the other 15 defensive linemen on the training camp roster, with the possibility that another name could be added along the way.

"I think you're always looking, but I still like some of the guys we have," defensive coordinator Rod Marinelli said. "I think there's a couple of young guys in here. We've just got to develop these guys now. That's the biggest thing."

The older guys become more important now that Lawrence is hurt. Before drafting him, the Cowboys signed three free agents in defensive tackles Henry Melton and Terrell McClain and end Jeremy Mincey.

Lawrence was running behind Mincey at camp when his foot got caught in the ground just as he was shoved by Pro Bowl tackle Tyron Smith in a one-on-one drill. Mincey still has work to do to get in shape, but he's a big step closer to starting Sept. 7 against San Francisco.

"DeMarcus created more combinations," said Mincey, whose last start was in 2012 with Jacksonville. "I could rush inside a lot because he's a young, speed guy off the edge. I'm an old, savvy vet off the edge, too. I'm going to try to make it happen at that right end, make some plays and do the best I can do at it."

Melton was a starter the minute he was cleared medically after missing most of last season with Chicago because of a torn knee ligament.

He's reunited with Marinelli, the former defensive coordinator for the Bears, and figures to fill some of the leadership role after Ware's release and linebacker Sean Lee's season-ending knee injury in the first offseason practice.

"They brought me here to be a dominant force inside," Melton said. "If I've got to be a leader for the guys on the team, for the young guys, I'm glad to step in and do it."

Tyrone Crawford could be the player most influenced by Lawrence's injury, for several reasons. They share the Boise State bond, and Crawford's 2013 season ended in the first full workout of training camp with a torn Achilles tendon.

"I'm close to him and I told him anything he needs, he can come to me," Crawford said. "He's the same size as me, but I told him, kind of like a big brother, 'I'll be there for whatever you need, just let me know.'"

On the field, Crawford isn't sure what the injury means for him. He's mostly worked outside in training camp but has long been viewed by the coaches as someone who could play inside. At 6-foot-4 and 285 pounds, he's quite a bit bigger than Lawrence.

"Coach Marinelli has us learn all the positions," Crawford said. "We get the different looks at tackle and end, different steps we need to take. It's kind of tough learning but that's what we're here for."

The outlook for Anthony Spencer is one thing that hasn't changed for Dallas. It's still not known when he'll be ready to return from knee surgery almost a year ago after playing in the season opener.

"We just need to get him healthy," Garrett said. "He's worked really hard to get himself back. We're certainly optimistic that he'll be back at some point."

NOTES: CB Morris Claiborne said he was dealing with tendinitis in his right knee and sat out Thursday's practice. He said he expected to return Saturday after an off day for the team. ... CB Brandon Carr could report to camp by the weekend. He's been out since the start of camp spending time with his mother, who died Wednesday after battling breast cancer. ... LG Ron Leary (hamstring) was activated from the physically unable to perform list and went through a limited practice Thursday.